Kahaf means cave. And among the Companions, Kahaf means cave dweller. The cave is called a cave. The youths hid there. How many Companions Kahaf ? What are their names ? What is the name of their companion dog ? There are many opinions about this. Qur'anic sayings: Some will say , there were three of them , their fourth was their dog and some will say , they were five , their sixth was their dog , based on conjecture about the unseen. Again some would say , they were seven , their eighth was their dog. Say : My **** knows best their number ; Few people know their number. So without general discussion you should not argue about them and ask any of them about them. (Al-Kahf: 22) Ibn 'Abbas (may Allah be pleased with him) used to say: I was one of the few people who knew their number , they were seven in number. Allah has kept their number obscure. Allaah says (interpretation of the meaning): They were but a few young men , and they believed in their ****. If the description of their number had been more important, Allah, the All-Aware of all things visible and invisible, would have given a description of their number at the beginning of the Surah. That is, the **** knows their number and name well. There are many opinions as to what is meant by "Rakim" in the verse. Someone said , the dog's name is Rakim. Shuaib al-Zubai said their dog's name was Hamran .